One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,7)(4,5)(6,8)(9,10,15,14)(11,17,12,16)(13,18,22,21)(19,24,20,23)(27,28)(31,34)(35,36)(38,39)(2,5)(6,7)(9,11,15,12)(10,16,14,17)(13,19,22,20)(18,23,21,24)(25,26,30,33)(27,34,28,31)(29,32,37,40)(35,39,36,38)(1,2)(3,6)(4,5)(7,8)(9,11,15,12)(10,17,14,16)(13,19,22,20)(18,24,21,23)(25,27,30,28)(26,31,33,34)(29,36,37,35)(32,39,40,38)(1,3)(2,6)(4,8)(5,7)(9,12,15,11)(10,17,14,16)(13,19,22,20)(18,23,21,24)(25,26)(27,31)(28,34)(29,32)(30,33)(35,38)(36,39)(37,40)(9,13)(10,18)(11,19)(12,20)(14,21)(15,22)(16,23)(17,24)(25,28,30,27)(26,31,33,34)(29,36,37,35)(32,38,40,39)(9,14,15,10)(11,17,12,16)(13,21,22,18)(19,24,20,23)(25,29,30,37)(26,32,33,40)(27,35,28,36)(31,38,34,39)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.